Methyl Ethyl Ketone (MEK)
MEK is a liquid solvent used in surface coatings, adhesives, printing inks, chemical intermediates, magnetic tapes and lube oil dewaxing agents. MEK also is used as an extraction medium for fats, oils, waxes and resins. It is a highly efficient and versatile solvent for surface
coatings. Because of its effectiveness as a solvent, MEK is especially valuable in formulating high solids coatings, which help to reduce emissions from coating operations. MEK is a natural component of many foods, including apple juice, beans, chicken, honey and a variety of
cheeses. Synonyms for MEK are 2-butanone, ethyl methyl ketone, and methyl acetone.
MEK is a Food and Drug Administration (FDA)-approved indirect food additive for adhesives and polymers. The panel, with the U.S. EPA as the sponsoring organization, prepared the technical support documents for MEK under the International Council of Chemical Associations (ICCA)
Voluntary High Production Volume (HPV) chemical review.
MEK Hazardous Air Pollutant Delisting
On December 19, 2005, EPA issued a final rule removing MEK from Section 112 (b) (1) of the Clean Air Act. Petitions to remove a substance from the HAP list are authorized under Section 112 (b) (3). EPA determined that ambient concentrations, bioaccumulation, or deposition of MEK may
not reasonably be anticipated to cause adverse human health or environmental effects.
The panel's delisting petition presented extensive information on MEK's potential health and environmental effects, environmental releases, and resulting ambient air concentrations. Hazard information included in the petition illustrated MEK’s low acute and chronic
toxicity and low environmental toxicity. Air dispersion modeling results showed that ambient concentrations of MEK, even at the highest fenceline levels are below levels of concern.
MEK EPCRA Section 313 Delisting
On June 30, 2005, EPA deleted MEK from its list of chemicals subject to reporting under Section 313 of the Emergency Planning and Community Right-to Know Act’s Toxic Release Inventory (TRI) and Section 6607 of the Pollution Prevention Act of 1990. Facilities are no longer required
to report releases of and other waste management information on MEK. EPA’s final delisting rule is the result of a decision by the Court of Appeals of the District of Columbia Circuit, on an appeal filed by the panel, to overturn the District Court and direct EPA to delist MEK from
MEK VCCEP Independent Review
On February 19, 2004, the panel participated in an independent review, coordinated by Toxicology Excellence for Risk Assessment (TERA), of MEK under EPA’s Voluntary Children’s Chemical Evaluation Program (VCCEP). The purpose of the review was to determine whether existing data are adequate to characterize the risks of MEK to children, and if not, to identify data needs. The panel’s submission to TERA included a
quantitative risk characterization demonstrating that normally anticipated children’s exposures to MEK pose negligible adverse health risks and that no further data are needed to adequately characterize risk to children under the VCCEP program.
On April 19, 2004, TERA issued its report of the MEK
peer consultation meeting. In summary, panel members concluded that the MEK data were adequate to characterize risks to children as outlined under the VCCEP program. No data needs were identified by any of the review committee members.
A manuscript “Methyl Ethyl Ketone Safety Characterization for Infants and Children: Assessment in the USEPA Voluntary Children’s Chemical Evaluation Program” describes the results of the TERA review and was published in Human and Ecological Risk Assessment 13: 747-772, 2007.